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Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay
Published on: September 9, 2012
Occurrence of coagulation factor deficiency in post-tonsillectomy hemorrhage
Michaela Zumtobel1, Klemens Frei
1Department of Otorhinolaryngology, Head and Neck Surgery, Medical University of Vienna, Austria.
Introduction:
Tonsillectomy is one of the most common surgical procedures in Otorhinolaryngology and approximately 500 tonsillectomies are performed annually at the University Hospital of Vienna. Substantial postoperative bleeding is observed in 1.8% of cases, which is comparable to frequencies of 2-4% reported in other studies. Currently, routine pre-surgical coagulation investigations to predict bleeding status do not include the analysis of individual coagulation factors.
Material And Methods:
Within 2007 complete coagulation diagnostics were carried out in three patients presenting with recurrent (2-7 times) post-tonsillectomy hemorrhage but normal pre-surgical coagulation status parameters.
Results:
After the appearance of recurrent late bleeding, single factor diagnostic analysis revealed the causes to be factor XIIa deficiency, reduced factor XIIIa or von Willebrand disease. Recurrent late bleeding was stopped by the application of coagulation active plasma.
Conclusion:
This study shows that, even if routine diagnostics show normal pre-surgical coagulation findings, the investigation of single factors in cases of post-surgical late bleeding may identify coagulation disorders allowing the application of tailored therapy. Including such analysis in pre-operative diagnostics could therefore significantly help to limit postoperative bleeding.
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